What Syringe Size to Use for B12 TikTok Injecting B12 Enhance Me Training Academy B12 Injections: How They Work and Who Needs Them Meo Nutrition Red liquid (vitamin B12) in a disposable syringe with a needle and in a glass ampoule on a white background. Lots of empty space Stock Photo Alamy Still taking vitamin B12 injections? Move over shot. A pill may be just as good. Dr. Leslie Greenberg's Blog A Guide to the Best Needles for B12 Injections Precision Labs